Liquid products are commonly delivered to customers via delivery truck or other similar mechanism. The amount of liquid product is often measured by a liquid flow meter as the product is being pumped from a supply tank or truck to the customer's storage tank. From the time fuel is refined to the time of its final delivery, fuel is filtered at a number of locations. Generally, fuel is filtered every time it is moved to provide the maximum level of safety and guarantee that no impurities, such as water are delivered with the fuel.
Especially, the aviation industry is characterized by extremely stringent controls on fuel quality. Dirty or water-contaminated fuel is not an option. From the time jet fuel is refined, it is usually filtered every time it is moved to provide the maximum level of safety. In recognition of the extreme criticality of clean fuel, expensive fuel quality measures are built into fuel handling systems, from the point of fuel storage to fuel delivery into an airplane. Such measures include quality checks at fuel storage facilities, in fuel pipelines, white bucket tests at fueling sites, use of filters and/or separators (hereinafter referred to simply as “filters”) in fuel delivery vehicles to catch contaminated fuel right up to the moment of delivery, etc.
While filter manufacturers make their products as safe as possible using exhaustive tests, they do not provide one hundred percent protection against any malfunctioning of the filters. Therefore, it is necessary to monitor the performance of such filters when used on fuel delivery vehicles. Moreover, fuel filters used by fuel delivery vehicles often get compromised due to overuse. For example, filters often get plugged over time and such plugged filters may cause build up of excessive pressure in the fuel delivery systems, therefore allowing passage of contaminated fuel through such filters. Operators of fuel delivery systems are supposed to check the functioning of the fuel filters on a regular basis. However, due to a number of reasons including time and cost constraints, often, such filters are used even when they are not functioning properly. One mechanism that may be used to measure the functioning of the fuel filters is to monitor the differential pressure across the filter using mechanical pressure gauge that is manually checked by the operator while delivering fuel. However, because fuel delivery operators are generally more pre-occupied with performing other aspects of his job, they often do not check the differential pressure using the mechanical gauge.
Therefore, there is a need for a method or an apparatus for automatically monitoring performance of filters used in fuel delivery systems.